NCTI Installer Technician Exam Practice Test Questions
And Answers Verified 100% Correct
A symbol - ANSWER Is a simple line design used to represent a component or device
in a schematic circuit diagram.
Resistance - ANSWER Doubles when the length of a conductor doubles.
Load resistance - ANSWER Is considered to be the total resistance when the source
and wire resistances are very small.
Which of the following is true? - ANSWER The resistance of a material with a negative
temperature coefficient will decrease as the temperature increases.
The resistance of a conductor increases as - ANSWER The cross-sectional area of a
conductor decreases.
Current - ANSWER Flow that is excessive for a specific size of conductor can cause
the conductor to become too hot and melt or burn the conductor's insulating cover.
The total DC loop resistance of a 1,850-foot piece of 0.500-inch coaxial cable, with a
DC loop resistance of 1.34 ohms per 1,000 feet, is ________ ohms. - ANSWER 2.479
How can an installer control the resistance of the drop cable being installed at the
customer premises? - ANSWER Install Series 6 cable instead of Series 59 cable
because Series 6 cable is larger diameter, with lower resistance, than Series 59 cable.
Which of the following is true? - ANSWER The total resistance (RT) of a DC series
circuit is the sum of the individual resistances in the circuit (RS + RW + RL).
When the cross-sectional area of a conductor doubles, - ANSWER Its resistance
decreases to half its original value.
What is the total DC loop resistance of a 350-foot piece of Series 59 drop cable when
the DC loop resistance of that Series 59 cable is 56.04 ohms per 1,000 feet? -
ANSWER 19.614 ohms.
Voltage is - ANSWER A measurement of the force or pressure that causes electrons to
,move.
The letter and symbol designation for current is ______ and ______, respectively. -
ANSWER I and A
Convert 0.893 volts into a power of 10 and metric prefix form: - ANSWER 893 x 10-3 V
= 893 mV.
How much current would an applied voltage of 60 volts cause in a circuit of 300 ohms of
resistance? - ANSWER 0.2 A.
What is the voltage in a circuit with 0.8 ampere of current and 100 ohms of resistance? -
ANSWER 80 V.
_______ ohms of resistance is required for a circuit with an applied voltage of 30 volts
and a circuit current of 1.3 amperes. - ANSWER 23.076
An ohmmeter should be connected - ANSWER Across a resistor that is disconnected
from the circuit voltage source.
______ watts of power are consumed in a circuit with an applied voltage of 60 volts and
a load of 150 ohms. - ANSWER 24
A light bulb is consuming 60 watts of power with 0.9 amperes of current flowing through
it. What is the bulb's resistance? - ANSWER 74.07 ohms.
______ kilowatt-hours (kWh) would be supplied by a standby power supply that
provides 60 volts and 10 amperes of current for a period of 3 1/2 hours. - ANSWER 2.1
In a DC series circuit, - ANSWER The same amount of current flows through each
component.
A DC series circuit with R1 = 15 kilohms (kohms), R2 = 25 kohms, and R3 = 47 kohms
has a total resistance of ________ ohms. - ANSWER 87 k
Through which resistor in a DC series circuit where R1 = 10 ohms, R2 = 15 ohms, R3 =
20 ohms, and R4 = 5 ohms is the greatest current flowing? - ANSWER They all have
the same amount of current flowing through them.
Across which resistor in a DC series circuit where R1 = 25 ohms, R2 = 50 ohms, R3 =
75 ohms, and R4 = 10 ohms is the greatest voltage drop? - ANSWER R3.
What is the total voltage of a DC series circuit where ER1 = 20V, ER2 = 45V, and ER3
= 57V? - ANSWER 122 V.
, R2 = ________ ohms in a DC series circuit where R1 = 33 ohms, R3 = 47 ohms, R4 =
56 ohms, and RT = 197 ohms. - ANSWER 61
The circuit current is ______ amps in a DC series circuit where R = 40 ohms and E =
120 V. - ANSWER 3
IT = _______ amps in a DC series circuit where R1 = 10 ohms, R2 = 20 ohms, R3 = 30
ohms, R4 = 40 ohms, and ET = 50 V. - ANSWER 0.5
ER2 = _______ volts in a DC series circuit where R1 = 150 ohms, R2 = 150 ohms, R3 =
550 ohms, IT = 0.2 amperes. - ANSWER 30
A DC series circuit where R1 = 50 ohms, R2 = 100 ohms, R3 = 183.33 ohms, IT = 0.6
amperes, and ET = 200 volts consumes ______ watts of power. - ANSWER 120
The term "bel" originated with the early days of - ANSWER Telephone.
A number that compares an amount that is less than the whole to the whole amount is -
ANSWER A fraction.
A fraction is converted to a percent by - ANSWER Dividing the numerator by the
denominator and multiplying by 100.
1:5 ratio is equal to - ANSWER 20%
A length of coaxial cable that has an attenuation of 10 dB will experience an input RF
signal power loss of _________, with __________ of the signal remaining. - ANSWER
90%, 10%
One-tenth bel or 1 dB is - ANSWER The 10th root of the 1 bel ratio.
The input-to-output power ratio of a coaxial cable that has 1 dB of attenuation is -
ANSWER 1.2589:1
The input-to-output power ratio for 2 bels of similar impedance cable is - ANSWER
100:1
An input-to-output power ratio of 10:1 has an input-to-output voltage ratio of - ANSWER
3.162:1, the square root of the power ratio.
The power ratio for 2 dB is - ANSWER 1.585:1
What does 0 decibel millivolt (dBmV) equal? - ANSWER 1 mV across 75 ohms.
And Answers Verified 100% Correct
A symbol - ANSWER Is a simple line design used to represent a component or device
in a schematic circuit diagram.
Resistance - ANSWER Doubles when the length of a conductor doubles.
Load resistance - ANSWER Is considered to be the total resistance when the source
and wire resistances are very small.
Which of the following is true? - ANSWER The resistance of a material with a negative
temperature coefficient will decrease as the temperature increases.
The resistance of a conductor increases as - ANSWER The cross-sectional area of a
conductor decreases.
Current - ANSWER Flow that is excessive for a specific size of conductor can cause
the conductor to become too hot and melt or burn the conductor's insulating cover.
The total DC loop resistance of a 1,850-foot piece of 0.500-inch coaxial cable, with a
DC loop resistance of 1.34 ohms per 1,000 feet, is ________ ohms. - ANSWER 2.479
How can an installer control the resistance of the drop cable being installed at the
customer premises? - ANSWER Install Series 6 cable instead of Series 59 cable
because Series 6 cable is larger diameter, with lower resistance, than Series 59 cable.
Which of the following is true? - ANSWER The total resistance (RT) of a DC series
circuit is the sum of the individual resistances in the circuit (RS + RW + RL).
When the cross-sectional area of a conductor doubles, - ANSWER Its resistance
decreases to half its original value.
What is the total DC loop resistance of a 350-foot piece of Series 59 drop cable when
the DC loop resistance of that Series 59 cable is 56.04 ohms per 1,000 feet? -
ANSWER 19.614 ohms.
Voltage is - ANSWER A measurement of the force or pressure that causes electrons to
,move.
The letter and symbol designation for current is ______ and ______, respectively. -
ANSWER I and A
Convert 0.893 volts into a power of 10 and metric prefix form: - ANSWER 893 x 10-3 V
= 893 mV.
How much current would an applied voltage of 60 volts cause in a circuit of 300 ohms of
resistance? - ANSWER 0.2 A.
What is the voltage in a circuit with 0.8 ampere of current and 100 ohms of resistance? -
ANSWER 80 V.
_______ ohms of resistance is required for a circuit with an applied voltage of 30 volts
and a circuit current of 1.3 amperes. - ANSWER 23.076
An ohmmeter should be connected - ANSWER Across a resistor that is disconnected
from the circuit voltage source.
______ watts of power are consumed in a circuit with an applied voltage of 60 volts and
a load of 150 ohms. - ANSWER 24
A light bulb is consuming 60 watts of power with 0.9 amperes of current flowing through
it. What is the bulb's resistance? - ANSWER 74.07 ohms.
______ kilowatt-hours (kWh) would be supplied by a standby power supply that
provides 60 volts and 10 amperes of current for a period of 3 1/2 hours. - ANSWER 2.1
In a DC series circuit, - ANSWER The same amount of current flows through each
component.
A DC series circuit with R1 = 15 kilohms (kohms), R2 = 25 kohms, and R3 = 47 kohms
has a total resistance of ________ ohms. - ANSWER 87 k
Through which resistor in a DC series circuit where R1 = 10 ohms, R2 = 15 ohms, R3 =
20 ohms, and R4 = 5 ohms is the greatest current flowing? - ANSWER They all have
the same amount of current flowing through them.
Across which resistor in a DC series circuit where R1 = 25 ohms, R2 = 50 ohms, R3 =
75 ohms, and R4 = 10 ohms is the greatest voltage drop? - ANSWER R3.
What is the total voltage of a DC series circuit where ER1 = 20V, ER2 = 45V, and ER3
= 57V? - ANSWER 122 V.
, R2 = ________ ohms in a DC series circuit where R1 = 33 ohms, R3 = 47 ohms, R4 =
56 ohms, and RT = 197 ohms. - ANSWER 61
The circuit current is ______ amps in a DC series circuit where R = 40 ohms and E =
120 V. - ANSWER 3
IT = _______ amps in a DC series circuit where R1 = 10 ohms, R2 = 20 ohms, R3 = 30
ohms, R4 = 40 ohms, and ET = 50 V. - ANSWER 0.5
ER2 = _______ volts in a DC series circuit where R1 = 150 ohms, R2 = 150 ohms, R3 =
550 ohms, IT = 0.2 amperes. - ANSWER 30
A DC series circuit where R1 = 50 ohms, R2 = 100 ohms, R3 = 183.33 ohms, IT = 0.6
amperes, and ET = 200 volts consumes ______ watts of power. - ANSWER 120
The term "bel" originated with the early days of - ANSWER Telephone.
A number that compares an amount that is less than the whole to the whole amount is -
ANSWER A fraction.
A fraction is converted to a percent by - ANSWER Dividing the numerator by the
denominator and multiplying by 100.
1:5 ratio is equal to - ANSWER 20%
A length of coaxial cable that has an attenuation of 10 dB will experience an input RF
signal power loss of _________, with __________ of the signal remaining. - ANSWER
90%, 10%
One-tenth bel or 1 dB is - ANSWER The 10th root of the 1 bel ratio.
The input-to-output power ratio of a coaxial cable that has 1 dB of attenuation is -
ANSWER 1.2589:1
The input-to-output power ratio for 2 bels of similar impedance cable is - ANSWER
100:1
An input-to-output power ratio of 10:1 has an input-to-output voltage ratio of - ANSWER
3.162:1, the square root of the power ratio.
The power ratio for 2 dB is - ANSWER 1.585:1
What does 0 decibel millivolt (dBmV) equal? - ANSWER 1 mV across 75 ohms.
